BACKGROUND ART
In cabin pressurizing and ventilating systems, an air pressure source such as an air pump, supercharger, or the like is typically provided to supply pressurized air to the cabin. Air pressure within the cabin is maintained at the required pressure by controlling the flow of air from the cabin through one or more outflow valves disposed in an opening or openings in the body structure forming the aircraft. The air provided by the air pressure source is also conventionally used to cool various electronic devices that are used to control and navigate the aircraft.
Failures interrupting the supply of pressurized air from these air pressure sources are possible but have been predicted to have an extremely low probability of occurrence. However, in the event of such a failure, it would be possible for cabin temperatures, humidity the concentration of undesired gasses such as carbon dioxide, to reach undesired levels. Consequently, it is highly desirable to provide an alternate air conditioning device for ventilating the cabin and cooling the electronic control and navigation devices in the event of a failure of the system that provides pressurized air to the cabin and electrical control and navigation devices.
Several alternate air conditioning systems are known in the art and these generally include a deployable ram-air scoop. Upon the occurrence of a failure, the ram-air scoop of these systems is projected into the airstream to direct or "scoop" a flow of fresh air directly into the aircraft's air distribution system to ventilate the cabin and cool desired electronic components. While such devices are effective, they nonetheless have several drawbacks.
One notable drawback concerns the relative cost of these ram-air scoops, especially in view of the fact that such failures in the air distribution system would be extremely rare. By their nature, the ram-air scoop systems are dedicated to a single function. Consequently, aircrafts that employ such devices incur a cost and an increase in the weight of the aircraft to which very little offsetting benefit is gained as a result of the low probability of a failure which would require the use of the ram-air scoop to provide ventilation to the aircraft. Additionally, integrating such systems into existing aircraft can be difficult and very costly due to the amount of labor involved.
In view of these drawbacks, there remains a need in the art for a cost-efficient alternative ventilation system that may be employed when a failure interrupts the supply of pressurized air that is used to ventilate an aircraft cabin and cool the aircraft control and navigation electronics.
It is therefore one object of the present invention to provide an alternate ventilation system to ventilate the cabin of an aircraft and cool the aircraft's electrical devices.
It is another object of the present invention to provide an alternate ventilation system which is cost efficient and easily integrated into an aircraft.
It is another object of the present invention to provide a method for ventilating an aircraft.